Effect of chronic postnatal hypoxia on dopamine uptake by synaptosomes from striatum of adult rats.

The exposure of rats to an early postnatal hypoxia (pO2 11.3 kPa, 12 h daily, 2nd-11th day of life) causes not only long lasting changes in the dopamine (DA) release from striatum slices but also in the DA uptake by striatal synaptosomes. Adult controls have a synaptosomal DA uptake of about 5 pmoles per mg protein and per min (males 4.99, females 5.69). Rats which have been exposed to an early postnatal hypobaric hypoxia exhibit a DA uptake of 2.71 (males) and 4.53 (females) pmoles per mg protein and per min. This long-lasting effect on the dopaminergic system of the striatum must be caused by a hypoxic alteration of gene expression in a critical period of the neonatal rat brain development, with permanent effects on the DA-metabolism and/or on the function of synaptic membranes.